This story originally aired on April 28, 2018. If you close your eyes and picture Sasquatch, there’s a good chance you’ll conjure up a very specific image: a big, hairy humanoid, mid-stride, arms swinging, head turned to glance back over its right shoulder. In that iconic picture, the thing Bigfoot was turning back to look at was Bob Gimlin. Gimlin, along with Roger Patterson, gathered their famous film footage in northern California in 1967. Fifty years later people still pore over it, debating